PHILOSOPHICAL 
TRANSACTIONS. 
IX. On the Conversion of the Substance of a Bird into a hard 
fatty Matter. In a Letter from Thomas Sneyd, Esq. to Sir 
Joseph Banks, Bart. P. R. S. 
Read March 29, 1792. 
SIR, 
I take the liberty of sending you two or three pieces of a 
bird whose substance has been converted into a hard fatty 
matter, which I found at the head of a fish pool, where a small 
brook runs into it, lying under water upon the mud. When 
first taken out, it was almost entire, and had several feathers 
sticking in different parts of the skin, which have since fallen 
out; a little down, however, still adheres to the smaller speci- 
men. From the size, and general appearance of the bird, I 
conjectured it to be a duck, or young goose; but before I had 
time to give it a particular examination, it was unfortunately 
broken in pieces, and the greatest part destroyed. The skin 
in the piece which was saved is of different thicknesses, in some 
parts a full quarter of an inch; it has retained its original 
MDCCXCI I. Dd 
